Patent · US Expired

Long decay luminescent material

US5853614A · kind A · utility

39Cited by
1References
5Claims
0Family size

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Key dates

Filing dateJul 21, 1997
Grant dateDec 29, 1998
Priority date
Expiry dateJul 21, 2017

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K11/7797
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Long decay luminescent materials having improved long decay time and improved high brightness is represented by the formula as PA1 Sr.sub.0.9995 .about..sub.0.998 Eu.sub.0.0005 .about..sub.0.002)Al.sub.2 O.sub.4 .multidot.(Sr.sub.0.9995 .about..sub.0.998 Eu.sub.0.0005 .about..sub.0.002)O .multidot.n(Al.sub.1-a-b B.sub.b Dy.sub.a).sub.2 O.sub.3 in it a=0.0005.about.0.0002, b=0.0001.about.0.35, n=1.about.8 and the method for manufacturing the long decay luminescent materials is characterized in heating the raw materials as SrCo.sub.3, .alpha. type alumina, .gamma. type alumina, boron-containing compound, Eu.sub.2 O.sub.3 and Dy.sub.2 O.sub.3 gradually from 400.degree. C. up to 1250.degree. C..about.1600.degree. C. during 7.about.10 hours, firing it at 1250.degree. C..about.1600.degree. C. for 3.about.5 hours and then cooing it gradually from 1250.degree. C..about.1600.degree. C. down to 200.degree. C. during 7.about.10 hours and the heating, firing and cooling processes are all conducted under the condition of existence of carbon.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.